CIEF is a powerful separation tool utilized in the characterization and relative quantitation of therapeutic mAb charged isoforms. However, one CIEF method is not capable of separating all mAbs with high resolution and reproducibility. Optimization of sample composition and separation parameters is expected when developing a CIEF method for a specific mAb. This paper summarizes a root cause investigation into why a validated CIEF separation method for MAK33 (a type of IgG1) was no longer reproducible. In addition, this paper introduces the concept of sample focusing volume, which is defined as the actual capillary volume occupied by the sample after focusing and explains why there is less protein precipitation and aggregation when using narrow-range ampholytes than broad-range ampholytes. The use of DMSO as protein solubilizer and possible replacement of urea is also explored in this work. Finally, this paper demonstrates that a new optimized CIEF method can achieve over 100 reproducible high-resolution separations of MAK33 per neutral-coated capillary. © 2020 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.Immune systems have repeatedly diversified in response to parasite diversity. Many animals have outsourced part of their immune defence to defensive symbionts, which should be affected by similar evolutionary pressures as the host's own immune system. https://www.selleckchem.com/products/vx803-m4344.html Protective symbionts provide efficient and specific protection and respond to changing selection pressure by parasites. Here we use the aphid Aphis fabae, its protective symbiont Hamiltonella defensa, and its parasitoid Lysiphlebus fabarum to test whether parasite diversity can maintain diversity in protective symbionts. We exposed aphid populations with the same initial symbiont composition to parasitoid populations that differed in their diversity. As expected, single parasitoid genotypes mostly favoured a single symbiont that was most protective against that particular parasitoid, while multiple symbionts persisted in aphids exposed to more diverse parasitoid populations, which in turn affected aphid population density and rates of parasitism. Parasite diversity may be crucial to maintaining symbiont diversity in nature. © 2020 John Wiley &amp; Sons Ltd/CNRS.BACKGROUND Urea cycle disorders are congenital metabolism errors that affect ammonia elimination. Clinical signs and prognosis are strongly influenced by peak ammonia levels. Numerous triggers associated with metabolic decompensation have been described with many of them, including fasting or stress, being related to the perioperative period. AIMS We aimed to assess perioperative complications in pediatric patients with urea cycle disorders requiring general anesthesia in our center. METHODS We reviewed the clinical history of all the pediatric patients with a confirmed urea cycle disorders diagnosis requiring surgery or a diagnostic procedure with anesthesia between January 2002 and June 2018. RESULTS We included 33 operations (major surgery, minor surgery, and diagnostic procedures) carried out on 10 patients via different anesthetic techniques. We observed the following complications intraoperative hyperglycemia in one case, postoperative vomiting in eight cases, and slightly increased postoperative ammonia levels (54, 59, and 69 ?mol/L) with normal preoperative levels in three cases without associated metabolic decompensation. There were two cases of perioperative hyperammonemia (72 and 69 ?mol/L) secondary to preoperative metabolic decompensation (137 and 92 ?mol/L) with the levels progressively dropping and normalizing in the first 24-48 hours, respectively. CONCLUSIONS Procedures under anesthesia on pediatric patients with urea cycle diseases should be performed by experienced multidisciplinary teams at specialized centers. Perioperative management focused on avoiding catabolism (especially during fasting) and monitoring signs associated with metabolic decompensation to allow for its early treatment should be included in routine anesthetic techniques for children with urea cycle disorders. This article is protected by copyright. All rights reserved.Current demand for SARS-CoV-2 testing is straining material resource and labor capacity around the globe. As a result, the public health and clinical community are hindered in their ability to monitor and contain the spread of COVID-19. Despite broad consensus that more testing is needed, pragmatic guidance towards realizing this objective has been limited. This paper addresses this limitation by proposing a novel and geographically agnostic framework (the 4Ps Framework) to guide multidisciplinary, scalable, resource-efficient, and achievable efforts towards enhanced testing capacity. The 4Ps (Prioritize, Propagate, Partition, and Provide) are described in terms of specific opportunities to enhance the volume, diversity, characterization, and implementation of SARS-CoV-2 testing to benefit public health. Coordinated deployment of the strategic and tactical recommendations described in this framework have the potential to rapidly expand available testing capacity, improve public health decision-making in response to the COVID-19 pandemic, and/or to be applied in future emergent disease outbreaks. This article is protected by copyright. All rights reserved.The number of patients requiring tracheal intubation rose dramatically in March and April 2020 with the COVID-19 outbreak. Our thoracic surgery department has seen an increased incidence of severe pneumomediastinum referred for surgical opinion in intubated patients with COVID-19 pneumonitis. Here we present a series of five cases of severe pneumomediastinum requiring decompression therapy over a 7-day period in the current COVID-19 outbreak. We hypothesise that the mechanism for this is the aggressive disease pathophysiology with an increased risk of alveolar damage and tracheobronchial injury along with the use of larger bore tracheal tubes and higher ventilation pressures. We present this case series in order to highlight the increased risk of this potentially life-threatening complication among the COVID-19 patient cohort and offer guidance for its management to critical care physicians. This article is protected by copyright. All rights reserved.